Frequently Asked Questions

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Q:
This is supported as a protein coding gene based on transcript and genomic data in human, and homology data. The differences with the human reference assembly (insertions at nt 475-476 and nt 496-497 in the CDS) are supported by transcript data and alignment to the alternate (Celera) assembly. The mouse protein NP_758465.2 (Ppp1r9b, Entrez GeneID 217124) is the same length as the human protein (NP_115984.3) and 96% identical. The region where the mouse gene is located on chromosome 11 has the same genes in the same order as the location on human chromosome 17 where this gene is annotated.
A:
Thanks to Dr. Janet Weber from the Refseq project group for pointing this to us. PGOHUM00000250821 is most likely a protein-coding gene PPP1R9B. The erroneous annotations probably results due to either an error or difference in the canonical human reference genome. Please note that this locus is tagged for follow-up by the Genome Reference Consortium as a possible locus where the reference genome is incorrect (GRC Jira system as HG-191, http://www.ncbi.nlm.nih.gov/projects/genome/assembly/grc/human/issues/chr17/ ).

[tag sb]
Q:
We’re wondering if you happen to have a database for cow pseudogenes
A:
We haven’t done a Pesudopipe run on cow genome.
I see that the genome is available from Ensembl. You can download the code and run it. In theory,
Pseudopipe can be executed when the genome and the annotation files are a part of Ensembl. The code to run Pseudopipe can be downlaoded fromhttp://www.pseudogene.org/DOWNLOADS/pipeline_codes/

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Input data:
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You may create a separate folder within the ppipe_input (and ppipe_output) for each species. There need to be three folders for each species genomic input data,
– dna: contains a file named dna_rm.fa, which is entire repeat masked dna from that species, and a list file for all unmasked dna divided into different chromosomes in FASTA format;
– pep: contains a FASTA file for all the proteins in the species;
– mysql: contains a list of files named as “chr1_exLocs”, “chr2_exLocs”, etc. to specify exons coordinates, one for each chromosome. Only thing matters for these files are their third and fourth columns, which should be start and end coordinates of exons.

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Environment setting:
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You’ll need python, blast and tfasty to run the pipeline. Their paths should be indicated at the end of /pseudopipe/bin/env.sh

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Run the pipeline
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First go to the folder pseudopipe/bin, and run with command line in the form of: ./pseudopipe.sh [output dir] [masked dna dir] [input dna dir] [input pep dir] [exon dir] 0.

An example using the try-out data is as follow:
./pseudopipe.sh ~/pgenes/ppipe_output/caenorhabditis_elegans_62_220a ~/pgenes/ppipe_input/caenorhabditis_elegans_62_220a/dna/dna_rm.fa ~/pgenes/ppipe_input/caenorhabditis_elegans_62_220a/dna/Caenorhabditis_elegans.WS220.62.dna.chromosome.%s.fa ~/pgenes/ppipe_input/caenorhabditis_elegans_62_220a/pep/Caenorhabditis_elegans.WS220.62.pep.fa ~/pgenes/ppipe_input/caenorhabditis_elegans_62_220a/mysql/chr%s_exLocs 0
(This command line assumes you extract the archive in your home directory, i.e., “~/”. Please note that the paths in the command line need to be absolute, and chromosome and exon files are specified with wild card “%s”.)

The blast step is already included in the pipeline.

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Output:
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The output can be found at ppipe_output/caenorhabditis_elegans_62_220a/pgenes/ppipe_output_pgenes.txt

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Run time
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On a single laptop (2.6GHz, 4GB RAM): The most time consuming step is tblastn. It may take around one day to finish an entire genome in a comparable size of C. elegans. The following steps will finish in a few hours.

We’ve implemented the pipeline to run parallel in cluster machines. However, the pipeline I sent can only run on a single machine. The parallel implementation is currently hard-coded to our local settings.

Some specific answers to your questions:
Q:
I am ready to run tBLASTn of proteome versus genome. I can repeat mask the genome during the tBLASTn run itself, would that be OK?

A:
You don’t have to run the tBLASTn by yourself since it is already integrated into the pipeline. In ENSEMBL, the genomes are repeat masked by RepeatMasker, that’s the input data currently used the pipeline. I would assume any reasonable repeat mask algorithm is fine.

Q:
For the tBLASTn, instead of using the entire genome, can I use the genome that is ‘masked’ for entire genes (not just exons). Based on gff info, I have converted the genic regions (not just exons) into stretches of Ns. Would this ‘masked’ genome be a good input for my tBLASTn?

A:
You don’t need to do that since the pipeline will remove blast hits significantly overlap known gene exons ( > 30 bp overlap). Also, manually masking the entire gene sequences may be problematic, since we do find in some species the pseudogenes with some overlap with genes annotation.

Q:
You mention in your paper that you use bite-sized portions of your proteome as query for your BLAST search. Does that mean I should chop up my proteome into peptides x amino acids in length? Is that x >= 10?

A:
No need to do that. You can keep the whole protein sequences in the input FASTA file.

Q:
Is there a latest README or even a User Guide for PseudoPipe that you can share with me?

A:
Unfortunately, we don’t have a user friendly README file for the entire pipeline, especially for it to run in different environment from ours. I hope this email can help you set it up and run the pipeline in your machine. And also you can find some comments on each individual pipeline script file.
Please feel free to let me know if you need further assistance.

We are basically looking for the pseudogenes of protein P53 (tumor protein 53, or tumor suppressor) and protein WSTF (also call it as BAZ1B) in human species. There have no information in Pseudogene.org. Could you please help us to find a way to get the result?
Later on I found one webservice, which is called PseudoGeneQuest, and I submitted my target protein sequences and I got the results as shown in the following forwarded emails.

The results showed that there are known-pseudogenes in your database, however, I couldn’t extract the data out. Could you please help me to do so?
We are basically looking for the pseudogenes of protein P53 (tumor protein 53, or tumor suppressor) and protein WSTF (also call it as BAZ1B) in human species.

A:

I have looked at our pseudogene database and there are no pseudogenes for P53 and WSTF. I have further rechecked this by redoing homology analysis to the genome based on both P53 and WSTF sequence and there are no other regions in the genome which are good hits to P53 and WSTF. I have also looked at the results from the other program and either the matches are to other coding exons of other genes or all they are not significant matches, i.e. the match-lengths are very small and the e-values are not significant.

For example, these are the other regions in the genome homologous to the coding sequence in BLAST. Please see attached image. The only significant matches to P53 proteins are
1. NT_010718.16

This corresponds to P53 itself

2. NT_004350.19 This corresponds to P73, another gene and not a pseudogene

3. NT_005612.16 This corresponds to P63, another gene and not a pseudogene

The other two matches are not significant matches and have length homology only to 20% of P53.